This specification relates to content presentation.
Advertisers provide sponsored content items in different forms in order to attract consumers. A sponsored content item such as an advertisement (“ad”) is a piece of information designed to be used in whole or part by a user, for example, a particular consumer. Sponsored content items can be provided in electronic form. For example, online ads can be provided as banner ads on a web page, as ads presented with search results, or as ads presented in a mobile application.